Positional strategies in long Ehrenfeucht-Fraissé games

Saharon Shelah; Jouko Väänänen; Boban Velickovic

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arXiv · 1308.0156

Positional strategies in long Ehrenfeucht-Fraissé games

Saharon Shelah·Jouko Väänänen·Boban Velickovic

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Abstract

We prove that it is relatively consistent with ZF + CH that there exist two models of cardinality \aleph_2 such that the second player has a winning strategy in the Ehrenfeucht-Fraïssé-game of length ω_1 but there is no σ-closed back-and-forth set for the two models. If CH fails, no such pairs of models exist.

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BibTeX RIS

Saharon Shelah, Jouko Väänänen, Boban Velickovic. 2013-08-01. Positional strategies in long Ehrenfeucht-Fraissé games. https://arxiv.org/abs/1308.0156

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